Questionable look to glass

We ran across a window yesterday that we haven’t had this issue with before. I am including photos, I hope they are able to be seen and clear. There was a thermal window that was covered in what seemed to be hardwater spots or similar. There was only this bad film on the lower half of the window,just the lower pane. After buffing with a hard water spot remover(which took care of the spotting/film) it was noticeable that this lower pane is actually a different “color” glass than the upper pane and all the other panes in the house. In addition to being a different color it also has a haze between the panes that is different. It is not your typical blown seal haze, it is less noticable and has an “oily” look to it. I took a picture of it, hard to see but you can see it somewhat in front of the grid. The house is fairly new and the homewoner said the window hasn’t been replaced. There is not tint on any of the glass.
-It seems a little coincidental that the only window with the severe hardwater spots was the window with this nonuniformity, but it may just be a coincidence.
-What would make the lower section of that window seem so much “lighter” in color and is it related to the oily type haze between the panes?
Thanks for any input

Just the one window? Maybe broken seal?

Can’t tell from viewing on my phone; could it be bad Low-E sputtering?

I’d chalk it up to a bad seal as well. If that window had severe hardwater stains it more than likely means it has been taking a beating from the environment.

Either that or its just a flaw that made it past QC at the glass factory.

It doesn’t have the appearance of a blown seal. The slight “film” between the panes is not moisture, fog, or any other look commonly associated with a blown seal. It has a slight oily look between the panes when viewed from certain angles. Also a blown seal would not cause the window to be the different shade of color I am trying to figure out. What is “low-e” sputtering that was mentioned?
Thanks again

How old is the window? Is it under warrenty? If so, have the manufacturer replace it and ask them what it is. Then let us know.

Low-E coating:
Energy Savers: Low-Emissivity Window Glazing or Glass

(what they said) The way this coating is applied onto the layers of glass is called sputtering. Anyway, when the low-e coating comes into contact with oxygen and moisture it begins to break down. I’ve seen it inside panes after it’s broken down and it can look gold, greenish, or even blue. But it does look similar to what is most often termed seal failure.

That’s right Shawn, and excessive fabricating debris can also create some interesting reactions with Low-E coatings.

Perhaps I’m mistaken, but I thought Fab Debris was always on the exterior side of the glass and the low-e coatings were always applied on the interior side of the glass. No?

No. The real reason we have to deal w/ FD is because of it’s tendency to react to low-e coatings. Before low-e it was the practice of manufacturers to put the roller side of tempered glass inside the IG unit thus keeping the defective side tucked safely away. Once they started getting reactions they turned the roller side out and the FD problem started to go into full swing.

Ahhh, I see. Thanks for the educational info Tony. But then, is what I said always true now since the issue with Fab debris and low-e coatings reacting? Is Fab debris only on the outside of IGU’s and Low-E coatings always on the inside now?

There are a few newer window options from some manufacturers that put a low-e style coating on the outside surfaces now. Of course they would have to do a better job w/ the tempering since FD reactions could happen on any low-e surface. There are always those mistakes where you get a roller side of glass on the inside of a IG unit even now.
Here’s a couple pics of windows that are about 15-20 years old w/ FD and low-e issues.

Thanks for the pics Tony. I’ve definitely seen windows like both of the pics you posted. I always wondered why the windows were messed up so bad in between the panes.

Have you noticed any challenges with these windows? ie: scraping, buffing, soaps, etc.

No issues w/ cleaning. They never really look clean though because of the interior issues.

I was reading complaints about low emisivity glass on here. I have been in the glass replacement industry for close to 25 years. I have always been very skeptical on factory coated low e windows for many reasons. I recommend that any one getting ready to purchase new Windows for your home? Buy clear annealed Windows and have them tinted. You can regulate the heat reflection and obsorbtion by picking out different color schemes or reflective films. They are bright and have much more performances features than that of factory coated glass. Such as safety, 99% ultra violet protection and maintenance free. Plus you will never have to deal with failed glass units again. The film I highly recommend are Madico. I only use this film cause I know it’s quality and no other product comes close. Good Luck!

I disagree completely. Tinted windows suck to clean due to added drag and potential damage to tint if to aggressive in cleaning. Additionally, I have encountered windows that have blown seals and thermal fracture because they were not designed for the temperature difference that tinting can cause.

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Well perhaps your not cleaning them correctly. I recommend using strictly a soft buff or car wash mit. And tinting them does not create seal failure. I replace ig units working for glass companies and now I have spent 10 years tinting. What causes seal failure are several things. Not install properly or the window is so cheaply built, as for the same with the tint

So if a painter happens to get paint on a window, I should use a car wash mit. You do realize that this is a forum for professional window cleaners, not car detailers, right? Clean a window with a mit, thank you I needed a laugh.

It seems as what you are encountering is low e coating that is causing the drag. It scrtches very easy. I have never heard of dificulty cleaning acrylic glass tint. Fastory coated glass is sprayed on. Either between the two pane’a of glass or on the out side of the unit. That is where you are encountering issues with scratches and cleaning.